Population aging is currently an issue of primary relevance, constituting an enormous challenge for institutions and society. On the other hand, osteoarthritis (OA) is the most prevalent arthropathy in the elderly, strongly related to loss of functional capacity, limitation of daily activities, increased musculoskeletal pain, and deterioration of quality of life. More specifically, knee and hip OA represent a significant burden for health systems, and in Chile, they are among the ten most frequent diseases in the elderly. The technological development of the last decades has allowed the incorporation of several therapeutic alternatives for the intervention of the elderly, such as virtual reality, which allows interaction with multiple digital environments. Active video games (AVG) or exergames, carried out through commercial non-immersive virtual reality systems, have been proposed as a feasible, innovative, and entertaining alternative to optimize conventional physical rehabilitation (CPR). AVG in healthy older people and those with neurocognitive conditions effectively improves clinical and psychosocial outcomes. However, it has been recommended to advance the study of the effects of AVGs in people with musculoskeletal pathologies, such as knee and hip OA. Accordingly, the purpose is to analyze the effects of an AVG-guided physical exercise protocol adjunct to CPR on functional mobility in older adults with knee and/or hip OA.

Osteoarthritis (OA) is highly prevalent, and its incidence increases with aging populations. OA is characterized by articular cartilage degeneration, stiffness, inflammation, and musculoskeletal pain. In addition, the associated deterioration of health-related quality of life may influence therapeutic adherence and progression to future joint replacement. It appears that symptoms rather than structural impairment determine the risk of falling in older people with OA, so pain, loss of strength, and postural balance are underlying mechanisms for both falls and the clinical picture of OA itself. Moreover, the psychosocial sequelae are often underestimated because OA and pain are usually considered benign and unavoidable consequences of aging.

Physical exercise in people with knee and hip OA improves clinical aspects and psychosocial aspects such as self-efficacy, social function, and reduction of depression and isolation, among others. Adherence to exercise is fundamental and is closely related to user satisfaction. There are several barriers to physical exercise by older adults, such as lack of social support, transportation problems, and prioritization of basic needs; however, a determining factor is lack of motivation. In this regard, a study indicates that in Latin America, lack of motivation is among the main reasons for abandoning physical exercise.

The technological development of the last decades has allowed the incorporation of virtual reality into the healthcare field, favoring user motivation. Virtual reality is an experience based on the interactive digital simulation of environments and objects. These systems are categorized as non-immersive, semi-immersive, and immersive. Non-immersive systems use monitors or television screens, semi-immersive systems use panoramic screens to enhance the immersive experience, and immersive systems use head-mounted displays or multi-projected environments that generate a strong sense of immersion. It has been posited that the cost and expertise required to operate immersive systems may hinder their widespread use in clinical settings. In addition, the immersive sensation could produce symptoms such as visual fatigue and dizziness (cybersickness). On the other hand, non-immersive systems using commercially available home consoles are now considered an attractive and more accessible alternative to more sophisticated immersive systems.

Unlike traditional video games that use a standard command or joystick, active video games (AVGs) (also called exergames) use motion monitoring systems such as accelerometers, gyroscopes, haptic technology, and video capture. AVGs have been defined as a "combination of video game technologies and exercise routines to motivate physical activity among individuals or groups," recognizing that exercise in older people requires a greater understanding of the complexity of interaction with computer systems.

Conventional physical rehabilitation (CPR) consists of traditional physical exercises that improve functional capacity. Over the past few years, it has been suggested that incorporating AVGs into CPR can optimize clinical and psychosocial outcomes in the elderly. AVGs have been reported to promote improvements in functional mobility, coordination, muscle strength, and cognitive function in older people. In addition, AVGs improve walking ability and postural balance, as well as social well-being (perception of loneliness, social connectedness, and positive attitudes). However, this research has focused on healthy elderly and patients with neurocognitive pathologies. On the other hand, little information is available on older people with musculoskeletal conditions such as OA. In this regard, a systematic review conducted in patients with knee and/or hip OA indicates that the evidence is insufficient and inconclusive regarding the effectiveness of AVGs. Moreover, one study concludes that AVGs are a feasible and acceptable intervention for patients with knee OA. Interestingly, both studies raise the benefits and potential of AVGs in this population, urging further clinical trials.

Research question: In older adults with knee and/or hip OA. Is AVG-guided physical exercise adjunct to CPR more effective than CPR alone in improving clinical and psychosocial outcomes?

Working hypothesis: In older adults with knee and/or hip OA, AVG-guided physical exercise adjunct to CPR is more effective than CPR alone in improving clinical and psychosocial outcomes.

General objective: To determine the effects of an AVG-guided physical exercise program adjunct to CPR on clinical and psychosocial outcomes in older adults with knee and/or hip OA attended at a community-based family health center.

Specific objectives:

1. To characterize the study sample from sociodemographic, anthropometric, clinical, and psychosocial perspectives.
2. To compare the results of the primary outcome (functional mobility) and secondary outcomes between the study groups (experimental and control) in the different instances of outcome measurement.
3. To evaluate the clinical significance of the interventions and the clinical relevance of the interventions as perceived by the participants.

Inclusion Criteria:

• Age ≥60 and ≤84 years.
• Diagnosis of mild or moderate OA of the knee and/or hip.
• Independent walking capacity of at least 15 meters.

Exclusion Criteria:

• Inability to interact with active video games.
• Undergoing treatment with opioids or other medications with a potential influence on the outcomes of interest.
• <13 points in the abbreviated version of the Mini-Mental State Examination (MMSE-EFAM).
• OA associated with infectious, autoimmune, fractures or surgery.
• Participate or have participated in another physical-cognitive rehabilitation program during the last 3 months.

Investigator: Statistical data analyst.